The present invention relates to a vibratory compaction system and particularly to such a system having a simplified and rugged construction and an infinitely variable amplitude of vibration.
Compactor vehicles provided with vibratory rollers are used in compacting road surfaces and the like including dirt or asphalt. The vibration is suitably brought about by means of eccentric weights attached to the roller in some manner and rotated comparatively rapidly for imparting a vibratory force to the roller. Of course the extent of vibration desired may depend upon the surface materials employed and the degree of compaction desired, and therefore the amplitude of vibration is preferably adjustable. Various systems have been proposed heretofore for adjusting the degree or amplitude of vibration, but many have suffered from certain difficulties. For instance, a common drawback relates to a requirement for stopping a vehicle in order to change or adjust the positioning of weights and therefore the extent of vibration. Other systems allow for change in vibratory amplitude during operation of the vehicle, but the adjustment is found to be somewhat limited or produces only a change from maximum to minimum vibration amplitude. Some vehicles require a rotating hydraulic connection between the moving drum and the control apparatus.
Other systems have been proposed which are relatively complex in their organization and lack structural durability. For example, a pin and camming slot arrangement has been suggested for producing relative rotation of eccentric weights. However, such a system does not provide for the ease of operation and ruggedness required in a compactor vehicle.